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排序方式: 共有8396条查询结果,搜索用时 16 毫秒
1.
D301树脂分离衣康酸的工艺研究 总被引:1,自引:0,他引:1
采用弱碱性阴离子交换树脂D301对发酵法生产的衣康酸进行了分离研究。通过静态交换实验,研究了D301树脂对衣康酸的静态交换动力学,确定了传质机制和影响因素;通过动态交换实验,研究了以硫酸为洗脱剂,以氨水为再生剂的工艺过程,确定了主要工艺参数。 相似文献
2.
低碳经济时代企业的社会责任 总被引:1,自引:0,他引:1
阐述了低碳经济与企业社会责任的含义,分析了企业社会责任与企业竞争力的关系,提出了在发展低碳经济过程中企业应当承担的社会责任。 相似文献
3.
In this work, we have put forth two different protocols to address a concrete secure multi-party computational (MPC) problem related to a triangle, of which the coordinates of the three vertices are confidentially kept by the three participants, respectively. The three parties wish to collaboratively compute the area of this triangle while preserving their own coordinate privacy. As one of the merits, our protocols employ weaker assumptions of the existence of pseudorandom generators. In particular, unlike massive secure MPC protocols that rely a lot on oblivious transfer, ours utilize a new computing idea called “pseudorandom-then-rounding” method to avoid this burdensome obstacle. The two protocols are based on different theorems, while they both make use of the same underlying idea. At last, we provide a detailed proof for the first protocol by a series of security reductions of our newly defined games, which seems somewhat stronger than the previous simulation-based proofs and a proof sketch for the second one. Analysis and discussion about the reasons are provided as well to round off our work. 相似文献
4.
光交箱端口状态对通信网络的正常运行具有重要作用,由于光交箱内部布线杂乱,容易对端口产生排线遮挡问题,导致传统的光交箱端口图像识别操作不便。文中提出了一种基于AR技术的光交箱资源校准技术,该技术可以对实时视频自适应选取关键帧,然后对关键帧进行光交箱端口状态和文字识别,最后返回加权融合后的识别结果,并利用实时AR交互指引巡检人员处理被遮挡端口,这不仅能提升巡检人员的工作效率,还能提高实时识别准确率。将该校准技术应用到光交箱端口的智能检测中,能对光交箱的端口识别提供极大便利。 相似文献
5.
To evaluate the impact of zinc sulfate (ZnSO4) concentration on the structural properties of the films, Cd1-xZnxS thin films were formed on glass substrates using chemical bath deposition (CBD) in this study. The effect of ZnSO4 precursor concentration on the surface morphology, optical properties, and morphological structure of the Cd1-xZnxS films was investigated. To study the impact of zinc doping content on the performance metrics of Cu(In1-xGax)Se2 (CIGS) cells in the experimental group and to improve the buffer layer thickness, simulations were run using one-dimensional solar cell capacitance simulator (SCAPS-1D) software. 相似文献
6.
Let G1 and G2 be two connected graphs. The Kronecker product G1×G2 has vertex set V(G1×G2)=V(G1)×V(G2) and the edge set . In this paper, we show that if G is a bipartite graph with κ(G)=δ(G), then G×Kn(n?3) is super-κ. 相似文献
7.
This paper studies event design in event-triggered feedback systems. A novel event-triggering scheme is presented to ensure exponential stability of the resulting sampled-data system. The scheme postpones the triggering of events over previously proposed methods and therefore enlarges the intersampling period. The resulting intersampling periods and deadlines are bounded strictly away from zero when the continuous time system is input-to-state stable with respect to measurement errors. 相似文献
8.
Xiaofeng Chen Qianhong Wu Haibo Tian Byoungcheon Lee Kwangjo Kim 《Information Sciences》2011,181(8):1493-1502
It is considered to be the most suitable solution for large scale elections to design an electronic voting scheme using blind signatures and anonymous channels. Based on this framework, Okamoto first proposed a receipt-free voting scheme [30] for large scale elections. However, in the following paper, Okamoto [31] proved that the scheme [30] was not receipt-free and presented two improved schemes. One scheme requires the help of the parameter registration committee and the other needs a stronger physical assumption of the voting booth. In this paper, we utilize the double-trapdoor commitment to propose a new receipt-free voting scheme based on blind signatures for large scale elections. Neither the parameter registration committee nor the voting booth is required in our scheme. We also present a more efficient zero-knowledge proof for secret permutation. Therefore, our scheme is much more efficient than Okamoto’s schemes [30] and [31] with the weaker physical assumptions. Moreover, we prove that our scheme can achieve the desired security properties. 相似文献
9.